i built our product image on SDK1.2 (with necessary modificaitons, e.g. the new "cyfx_gcc_startup.s" file and the "cyu3lpp.a" in linker option...etc.)..the building was fine...but the code blocked at the point an external interrupt occurred on a simple IO pin. (the pin is configured properly with "Negative_Edge" interrupt enabled)

The same source code was built on SDK V1.0, V1.0.1 and V1.1 and worked fine.

Then i tried the "GPIOApp" example included in the SDK1.2 and tested it on DVK board and it seems having the same issue.

Is there additional anything should be done for interrupts of simple IO with SDK1.2?

If you change the input inerrupt trigger from "CY_U3P_GPIO_INTR_BOTH_EDGE" to "CY_U3P_GPIO_INTR_NEG_EDGE", the application will run. The use of "CY_U3P_GPIO_INTR_POS_EDGE" will get the application to hang.